Test of ability to hear expressed as a 2-dimensional graph. The abscissa is frequency in cycles per second and the ordinate is hearing level in db. Hearing levels for both continous and intermittent tones are charted. There are 4 distinct patterns that can be generated. Type I, found in normal people and in middle ear disorders; type II, associated with cochlear defects; type III, associated with disorders in CN 8; type IV, associated with disorders in CN 8.